Bump django from 2.1.15 to 2.2.10

Bumps [django](https://github.com/django/django) from 2.1.15 to 2.2.10.
- [Release notes](https://github.com/django/django/releases)
- [Commits](django/django@2.1.15...2.2.10)

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

requirements.txt

@@ -2,7 +2,7 @@ certifi==2018.8.24
 chardet==3.0.4
 coverage==4.5.1
 coveralls==1.5.1
-Django==2.1.15
+Django==2.2.10
 django-cors-middleware==1.2.0
 django-extensions==1.7.1
 django-filter==2.0.0